Filamentary Keratopathy and Dry Eye Syndrome

The use of preserved artificial tears several times a day provided little relief to this 54-year-old woman with red and painful eyes. The patient had a history of rheumatoid arthritis and dry eye syndrome; the latter is very common in patients with rheumatoid arthritis.

Filamentary keratopathy, which resulted from the underlying severe dry eye syndrome, was diagnosed. This condition was exacerbated by the artificial tear lubricant; preservatives in these preparations may cause toxic reactions in those who frequently use them. Persons with dry eyes are at particular risk because the preservatives are not diluted by normal tear flow.

Treatment of filamentary keratopathy is challenging and begins with removal of the characteristic filaments. The filaments-made up of desquamated epithelial cells, proteinaceous and lipoidal material, and mucous threads-can be diffusely distributed and are often seen in areas that stain with fluorescein on the corneal surface. Although they are most common in patients with dry eye syndrome, they can also be associated with recurrent corneal erosions and other corneal epithelial inflammation. The filaments cause acute pain and redness of the eye that is aggravated each time the patient blinks.

The filaments can be debrided easily after the cornea is anesthetized with a topical agent, such as tetracaine or proparacaine. Grasp the filament's base with a blunt-tipped forceps; a cotton-tipped applicator can be used instead, but a larger corneal defect may result. Apply fluorescein dye to the eye to highlight the filaments and facilitate their removal.

Prescribe frequent and liberal use of a nonpreserved artificial tear agent during the day and a bland lubricating ointment at bedtime. If mucus accumulation is excessive, use the mucolytic agent N-acetylcysteine, 5% to 20%, to dissolve the excess mucin and render the cornea more wettable. However, this agent is not approved by the FDA for this indication, and it may cause burning when instilled in the eye.

To prevent filaments from recurring in patients with chronic dry eye syndrome, the ophthalmologist may consider permanent punctal occlusion with silicone plugs or cautery, preservative-free hydroxypropyl cellulose ophthalmic inserts, and moisture chamber spectacles. Lateral tarsorrhaphy may be tried as well.